public class BuildTree {

      public static TreeNode buildTree(){
          TreeNode node1=new TreeNode(1);
          TreeNode node2=new TreeNode(2);
          TreeNode node3=new TreeNode(3);
          TreeNode node4=new TreeNode(4);
          TreeNode node5=new TreeNode(5);
          TreeNode node6=new TreeNode(6);
          TreeNode node7=new TreeNode(8);
          TreeNode node8=new TreeNode(9);

          node1.left=node2;node1.right=node3;
          node2.left=node4;node2.right=node5;
          node3.left=node6;node3.right=node7;
          node4.left=node8;
          return node1;

      }
}
